no. it's not valid on certain dates (mostly holidays), but that's it as far as I know. never had it denied where it was normally accepted and never paid attention to the booking time.
Absolutely no time restrictions. However, be aware that it is not honored on holidays. Check the list. Also, some dinner shows (HDD and Aloha) only honor it at the later shows. We have had it for two years now, and it's up at the end of July. We won't hesitate to renew. It's wonderful.